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Thread: The Evolution Thread

  1. #121
    Quote Originally Posted by sancho View Post
    Placed here because I can't find either a population genetics or a general science thread:

    http://www.sciencemag.org/content/342/6157/409.full

    Cliff notes version: population genetics is a wonderful, twisted, mess.
    This was a pretty cool find because it sort of refutes a common misperception (common among the general public anyway). A lot of people think that Native Americans were run of the mill Eastern Asians who crossed the land bridge and then, once geographically isolated, diverged into a genetically distinct group. What this and other findings show is that the progenitors of the Native Americans were actually genetically distinct from the main East Asian population prior to migrating to the new world. This finding in particular shows that this group of "proto-Native Americans" moved more extensively across Siberia, to the East across the land bridge where they remained for thousands of years, but also to some degree to the West reaching at least the Lake Baikul region. Even though these "proto-Native Americans" didn't last long in the region, they at least had the opportunity to be there for long enough to produce at least one offspring with a person of characteristically Western European heritage. That this Western European person made it that far East was also smewhat of a surprise. It suggests that at least some individuals during that time period were travelling pretty far from their better established homelands.

  2. #122
    Sam the Sheepdog LA Ute's Avatar
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    Boffins identify ancient Earth asteroid strike that dwarfed dinosaur killer: Massive space rock impact may have set the continents sliding. “The impacting body, which could have been an asteroid or a comet, was between 37 and 58 kilometers (23 to 36 miles) wide and hit the Earth at 20 kilometers per second (12 miles per second). The impact would have caused a crater around 500 kilometers (about 300 miles) across and the resulting tsunamis would have been thousands of meters high.”

    "It is only with the heart that one can see rightly; what is essential is invisible to the eye."
    --Antoine de Saint-Exupery

    "Things fall apart; the centre cannot hold."
    --Yeats

    “True, we [lawyers] build no bridges. We raise no towers. We construct no engines. We paint no pictures - unless as amateurs for our own principal amusement. There is little of all that we do which the eye of man can see. But we smooth out difficulties; we relieve stress; we correct mistakes; we take up other men's burdens and by our efforts we make possible the peaceful life of men in a peaceful state.”

    --John W. Davis, founder of Davis Polk & Wardwell

  3. #123
    Sam the Sheepdog LA Ute's Avatar
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    "It is only with the heart that one can see rightly; what is essential is invisible to the eye."
    --Antoine de Saint-Exupery

    "Things fall apart; the centre cannot hold."
    --Yeats

    “True, we [lawyers] build no bridges. We raise no towers. We construct no engines. We paint no pictures - unless as amateurs for our own principal amusement. There is little of all that we do which the eye of man can see. But we smooth out difficulties; we relieve stress; we correct mistakes; we take up other men's burdens and by our efforts we make possible the peaceful life of men in a peaceful state.”

    --John W. Davis, founder of Davis Polk & Wardwell

  4. #124
    Sam the Sheepdog LA Ute's Avatar
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    "It is only with the heart that one can see rightly; what is essential is invisible to the eye."
    --Antoine de Saint-Exupery

    "Things fall apart; the centre cannot hold."
    --Yeats

    “True, we [lawyers] build no bridges. We raise no towers. We construct no engines. We paint no pictures - unless as amateurs for our own principal amusement. There is little of all that we do which the eye of man can see. But we smooth out difficulties; we relieve stress; we correct mistakes; we take up other men's burdens and by our efforts we make possible the peaceful life of men in a peaceful state.”

    --John W. Davis, founder of Davis Polk & Wardwell

  5. #125
    Sam the Sheepdog LA Ute's Avatar
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    This is a great read:

    http://www.smithsonianmag.com/histor...180952462/?all

    It is like a crime novel. The Army Corps of Engineers is the unlikely villain.

    "It is only with the heart that one can see rightly; what is essential is invisible to the eye."
    --Antoine de Saint-Exupery

    "Things fall apart; the centre cannot hold."
    --Yeats

    “True, we [lawyers] build no bridges. We raise no towers. We construct no engines. We paint no pictures - unless as amateurs for our own principal amusement. There is little of all that we do which the eye of man can see. But we smooth out difficulties; we relieve stress; we correct mistakes; we take up other men's burdens and by our efforts we make possible the peaceful life of men in a peaceful state.”

    --John W. Davis, founder of Davis Polk & Wardwell

  6. #126
    Wow. 50X depth is really good sequencing data.

    as for the Kennewick man, I wonder why the Corps of Engineers is not allowing acquisition of additional material for DNA extraction. After losing the case, what is their rationale?

  7. #127
    Sam the Sheepdog LA Ute's Avatar
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    Quote Originally Posted by jrj84105 View Post
    Wow. 50X depth is really good sequencing data.

    as for the Kennewick man, I wonder why the Corps of Engineers is not allowing acquisition of additional material for DNA extraction. After losing the case, what is their rationale?
    My Occam's Razor explanation is that they are just being jerks. The DOJ can be that way about some things.

    OTOH, maybe Kennewick Man was really an alien from another planet whose space ship crashed in Kennewick, and the Air Force accidentally left him behind when they moved the rest of his shipmates to Area 51....

    Nah. They're just being jerks.

    "It is only with the heart that one can see rightly; what is essential is invisible to the eye."
    --Antoine de Saint-Exupery

    "Things fall apart; the centre cannot hold."
    --Yeats

    “True, we [lawyers] build no bridges. We raise no towers. We construct no engines. We paint no pictures - unless as amateurs for our own principal amusement. There is little of all that we do which the eye of man can see. But we smooth out difficulties; we relieve stress; we correct mistakes; we take up other men's burdens and by our efforts we make possible the peaceful life of men in a peaceful state.”

    --John W. Davis, founder of Davis Polk & Wardwell

  8. #128
    Sam the Sheepdog LA Ute's Avatar
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    Interesting thoughts here:

    http://m.weeklystandard.com/articles...52.html?page=1


    Sent from my iPhone using Tapatalk

    "It is only with the heart that one can see rightly; what is essential is invisible to the eye."
    --Antoine de Saint-Exupery

    "Things fall apart; the centre cannot hold."
    --Yeats

    “True, we [lawyers] build no bridges. We raise no towers. We construct no engines. We paint no pictures - unless as amateurs for our own principal amusement. There is little of all that we do which the eye of man can see. But we smooth out difficulties; we relieve stress; we correct mistakes; we take up other men's burdens and by our efforts we make possible the peaceful life of men in a peaceful state.”

    --John W. Davis, founder of Davis Polk & Wardwell

  9. #129
    Quote Originally Posted by LA Ute View Post
    Interesting thoughts here:

    http://m.weeklystandard.com/articles...52.html?page=1


    Sent from my iPhone using Tapatalk
    This is interesting, though the observations are not surprising. (It's not really what I would expect you to post.)
    One thing I have learned in a long life: that all our science, measured against reality, is primitive and childlike -- and yet it is the most precious thing we have.

    --Albert Einstein

    The fact that life evolved out of nearly nothing, some 10 billion years after the universe evolved out of literally nothing, is a fact so staggering that I would be mad to attempt words to do it justice.

    --Richard Dawkins

    Be kind to all, for everyone you meet is fighting a great battle.

    --Philo

  10. #130
    Sam the Sheepdog LA Ute's Avatar
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    Quote Originally Posted by SeattleUte View Post
    This is interesting, though the observations are not surprising. (It's not really what I would expect you to post.)
    I'm full of surprises.


    Sent from my iPhone using Tapatalk

    "It is only with the heart that one can see rightly; what is essential is invisible to the eye."
    --Antoine de Saint-Exupery

    "Things fall apart; the centre cannot hold."
    --Yeats

    “True, we [lawyers] build no bridges. We raise no towers. We construct no engines. We paint no pictures - unless as amateurs for our own principal amusement. There is little of all that we do which the eye of man can see. But we smooth out difficulties; we relieve stress; we correct mistakes; we take up other men's burdens and by our efforts we make possible the peaceful life of men in a peaceful state.”

    --John W. Davis, founder of Davis Polk & Wardwell

  11. #131
    Sam the Sheepdog LA Ute's Avatar
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    A 130,000 Year-Old Mastodon Threatens to Upend Human History

    https://www.wired.com/2017/04/130000...human-history/

    "It is only with the heart that one can see rightly; what is essential is invisible to the eye."
    --Antoine de Saint-Exupery

    "Things fall apart; the centre cannot hold."
    --Yeats

    “True, we [lawyers] build no bridges. We raise no towers. We construct no engines. We paint no pictures - unless as amateurs for our own principal amusement. There is little of all that we do which the eye of man can see. But we smooth out difficulties; we relieve stress; we correct mistakes; we take up other men's burdens and by our efforts we make possible the peaceful life of men in a peaceful state.”

    --John W. Davis, founder of Davis Polk & Wardwell

  12. #132
    Sam the Sheepdog LA Ute's Avatar
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    Mud DNA means we can detect ancient humans even without fossils


    We have an astonishing new way to study our early human ancestors: looking for their DNA in ancient sediments in places such as caves.A team of researchers has found the DNA of Neanderthals and Denisovans in some of the sites where they are known to have lived.

    “I think we show convincingly that these sequences are authentic,” says lead author Viviane Slon of the Max Planck Institute for Evolutionary Anthropology in Germany.

    The approach can now be used to find out whether early humans were present even when no bones have been found – and what kind of humans they were. It might also help resolve the debate about when the Americas were first inhabited by people, for instance....

    "It is only with the heart that one can see rightly; what is essential is invisible to the eye."
    --Antoine de Saint-Exupery

    "Things fall apart; the centre cannot hold."
    --Yeats

    “True, we [lawyers] build no bridges. We raise no towers. We construct no engines. We paint no pictures - unless as amateurs for our own principal amusement. There is little of all that we do which the eye of man can see. But we smooth out difficulties; we relieve stress; we correct mistakes; we take up other men's burdens and by our efforts we make possible the peaceful life of men in a peaceful state.”

    --John W. Davis, founder of Davis Polk & Wardwell

  13. #133
    Sam the Sheepdog LA Ute's Avatar
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    Massive Genetic Study Reveals 90 Percent Of Earth’s Animals Appeared At The Same Time

    http://www.techtimes.com/articles/22...-same-time.htm

    Interesting article.

    "It is only with the heart that one can see rightly; what is essential is invisible to the eye."
    --Antoine de Saint-Exupery

    "Things fall apart; the centre cannot hold."
    --Yeats

    “True, we [lawyers] build no bridges. We raise no towers. We construct no engines. We paint no pictures - unless as amateurs for our own principal amusement. There is little of all that we do which the eye of man can see. But we smooth out difficulties; we relieve stress; we correct mistakes; we take up other men's burdens and by our efforts we make possible the peaceful life of men in a peaceful state.”

    --John W. Davis, founder of Davis Polk & Wardwell

  14. #134

    The Evolution Thread

    Quote Originally Posted by LA Ute View Post
    Massive Genetic Study Reveals 90 Percent Of Earth’s Animals Appeared At The Same Time

    http://www.techtimes.com/articles/22...-same-time.htm

    Interesting article.
    No surprise here, but they’ve taken significant liberty on their title wording.

    Summary and Conclusion

    Science greedily seizes simplicity among complexities. Speciation occurs via alter- native pathways distinct in terms of the number of genes involved and the abruptness of transitions [148]. Nuclear variance in modern humans varies by loci in part due to unequal selection [149] and the linkage of neutral sites to those that undergo differential selection. Complexity is the norm when dealing with variance of the nuclear ensemble [150-154]. It is remarkable that despite the diversity of speciation mechanisms and path- ways the mitochondrial sequence variance in almost all extant animal species should be constrained within narrow parameters.

    Mostly synonymous and apparently neutral variation in mitochondria within spe- cies shows a similar quantitative pattern across the entire animal kingdom. The pattern is that that most—over 90% in the best characterized groups—of the approximately five million barcode sequences cluster into groups with between 0.0% and 0.5% variance as measured by APD, with an average APD of 0.2%.

    Modern humans are a low-average animal species in terms of the APD. The molecu- lar clock as a heuristic marks 1% sequence divergence per million years which is consis- tent with evidence for a clonal stage of human mitochondria between 100,000- 200,000 years ago and the 0.1% APD found in the modern human population [34, 155, 156]. A conjunction of factors could bring about the same result. However, one should not as a first impulse seek a complex and multifaceted explanation for one of the clearest, most data rich and general facts in all of evolution. The simple hypothesis is that the same explanation offered for the sequence variation found among modern humans applies equally to the modern populations of essentially all other animal species. Namely that the extant population, no matter what its current size or similarity to fossils of any age, has expanded from mitochondrial uniformity within the past 200,000 years.

    Nonhuman animals, as well as bacteria and yeast, are often considered “model sys- tems” whose results can be extrapolated to humans. The direction of inference is re- versible. Fossil evidence for mammalian evolution in Africa implies that most species started with small founding populations and later expanded [157] and sequence analysis has been interpreted to suggest that the last ice age created widespread conditions for a subsequent expansion [158]. The characteristics of contemporary mitochondrial vari- ance may represent a rare snapshot of animal life evolving during a special period. Al- ternatively, the similarity in variance within species could be a sign or a consequence of coevolution [159].

    Mitochondria drive many important processes of life [160-162]. There is irony but also grandeur in this view that, precisely because they have no phenotype, synonymous codon variations in mitochondria reveal the structure of species and the mechanism of speciation. This vista of evolution is best seen from the passenger seat.
    https://phe.rockefeller.edu/news/wp-...al-reduced.pdf

    Sent from my iPhone using Tapatalk

  15. #135
    Sam the Sheepdog LA Ute's Avatar
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    The Evolution Thread

    Why human speech is special:

    Evolutionary changes in both the vocal tract and the brain were necessary for humans’ remarkable gift of gab.

    https://www.the-scientist.com/featur...special--64351

    "It is only with the heart that one can see rightly; what is essential is invisible to the eye."
    --Antoine de Saint-Exupery

    "Things fall apart; the centre cannot hold."
    --Yeats

    “True, we [lawyers] build no bridges. We raise no towers. We construct no engines. We paint no pictures - unless as amateurs for our own principal amusement. There is little of all that we do which the eye of man can see. But we smooth out difficulties; we relieve stress; we correct mistakes; we take up other men's burdens and by our efforts we make possible the peaceful life of men in a peaceful state.”

    --John W. Davis, founder of Davis Polk & Wardwell

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